Disazo dye



. UNITED STATES PATENT OFFICE.

THOMAS HAROLD LEAMING AND THERESA MARIE SUSEMIHL, OF BUFFALO, NEW YORK,ASSIG-NORS T0 NATIONAL ANILINE & CHEMICAL COMPANY, INC., OF NEW YORK, N.Y., A CORPORATION OF NEW YORKL DISAZO DYE.

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To aZZ whom it may comcem:

Be it known that we, THOMAS H. LnAM- ING and THERESA M. SUSEMIHL,citizens of the United States, residing at Bufialo, in the county ofErie, State of New York, have invented certain new and useful Improve-.ments in Disazo Dye; and we do hereby de- The following specificexample will fur ther illustrate the invention:

15.0 kg. of acet-p-phenylenediamin are dissolved in 400 liters of hotwater, the solution cooled with ice, and 30 kg. of hydro- .chloric acid,sp. gr. 1.19 added, equivalent to 11.2 kg. anhydrous hydrochloric acid.The cool solution is now diazotized in the usual manner with 6.9 kg. ofsodium nitrate. 24.0 kg. of 1.8 amihonaphtholl-sulfonic acid aredissolved in 20 liters of 10% aqueous caustic soda, the solution dilutedto 400 liters, acidified with acetic acid and cooled in an ice bath. Thecool solution of diazotized acet-p-phenylenediamin is now added and isstirred until coupling is complete (about 12 hours). The precipitatedmonazo dye is now filtered off and dissolved in 1600 liters of water and40 kg. of sodium carbonate. To the cool solution of the monazo dye thereis .now added a diazotized solution of 15.0 kg. acet-p-phenylenediamin(prepared as above), and the mixture stirred until the coupling iscomplete (about 3 hours). It is then salted out with common salt,preferably at 80 C; and filtered. The precipitated dye is now saponified(to split oil the acetyl groups and replace the same by hydrogen) byheating to 90-100 C. in 2400 liters of 10 per cent. caustic soda solu-Specification of Letters Patent.

Patented Dec. 28, 1920.

Application filed July 1, 1919. Serial No. 307,896.

also to the dyed fabrics, or other materials, dyed with such newdyestufl.

The new dyestufi? can be obtained by the diazotization of acetp-phenylenediamin, or of p-nitranilin, coupling the disazo compound soobtained with one molecular proportion of 1.S-aminonaphthol-eL-sulfonicacid (S-acid), coupling the resulting intermediate with anothermolecular proportion of the diazotized acet-p-phenylenediamin, or of thediazotized p-nitranilin, and then splitting off the acetyl groups, orreducing the nitro groups. The new dyestufi has in the1 free state thefollowing probable formu a? tion. At the endv of this time (about 3-4hours), hydrochloric acid is added until the reaction is almost neutrale. slightly alkaline toward brilliant yellow test paper), and theproduct cooled and filtered.

The new disazo dye thus obtained, in the form of its sodium salt, is abrown powder soluble in water to give a blue-green solution, soluble inalcohol, and soluble in concentrated sufuric acid to form a greensolution which on dilution with ice water, i. e., water in the presenceof ice, turns to a blue color and finally produces a blue precipitate.

The new dye dyes vegetable, animal and artificial fibers, such ascotton, wool, natural and artificial silk, etc, as well as union fabricscomposed of mixtures of these fibers, producing in generalgreenish-black shades, which can be diazotized and developed on thefiber or fabric with beta-naphthol, or meta-phenylenediamin, ormeta-tolylenediamin or resorcin, or other similar compounds, to give ingeneral reddish to greenish shades of black which differ in tint fromthe selfshade.

The dyed materials produced either by the action of the new dyestuifitself, or by developing the new dyestuff on the fiber or fabric, aswell as the new dyestuff itself, form a part of the present invention.

We claim having in the free state the following probable formula saiddye, in the form of its sodium salts, being a brownpowder soluble inwater to give a blue-green solution, soluble in alcohol, soluble inconcentrated sulfuric acid to give a green solution, and yielding uponreduction with stannous chlorid and hydrochloric acid p-phenylenediaminand tri-amino-S- naphtholl-sulfonic acid; and dyeing cotton, wool,natural and artificial silk, or mixtures of the same, greenish shades ofblack which can be developed on the fiber.

2. The herein described new dyes obtain able by diazotizing the newdisazo dye of claim 1 and developing with a developing agent. 7 I

3'. The herein described new dye obtainable by diazotizing the newdisazo dye of claim 1 and developing with m toluylenediamin. 1

4. Materials dyed with the new disazo dye of claim 1.

5. Union goods dyed with the new'disazo dye of claim 1.

6. Materials dyed with the new disazo dye of claim 1, said dye beingdeveloped on the material.

7. Union goods dyed with the neivdisazo dye of claim 1, said dye beingdeveloped on the material.

THOMAS HAROLD LEAMING. THERESA MARIE SUSEMIHL.

